In trying to determine if core count had any effect on this bug, I set maxcpus to 4 and tried loading the driver on the kernel with the shadow stack enabled (aka the standard -generic config). It looks like the same root issue occurred, but this time, I got a panic with a trace that corroborates the claim that this is related to the shadow stack:

[  391.736417] Internal error: Oops - FPAC: 0000000072000000 [#1] SMP
[  391.744257] Modules linked in: nvidia(OE+) ecdh_generic ecc qrtr cdc_ether cdc_subset usbnet cfg80211 binfmt_misc dax_hmem cxl_acpi cxl_core ast i2c_algo_bit nvidia_cspmu arm_spe_pmu arm_smmuv3_pmu arm_cspmu_module uio_pdrv_genirq uio spi_nor acpi_ipmi mtd nls_iso8859_1 ipmi_ssif ipmi_devintf cppc_cpufreq ipmi_msghandler acpi_power_meter dm_multipath efi_pstore nfnetlink dmi_sysfs ip_tables x_tables autofs4 btrfs blake2b_generic raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor xor_neon raid6_pq libcrc32c raid1 raid0 mlx5_ib ib_uverbs macsec ib_core mlx5_dpll i2c_smbus crct10dif_ce polyval_ce polyval_generic ghash_ce sm4_ce_gcm sm4_ce_ccm sm4_ce sm4_ce_cipher sm4 sm3_ce sm3 nvme sha3_ce sha2_ce sha256_arm64 sha1_ce mlx5_core nvme_core mlxfw nvme_auth psample xhci_pci tls xhci_pci_renesas pci_hyperv_intf spi_tegra210_quad i2c_tegra aes_neon_bs aes_neon_blk aes_ce_blk aes_ce_cipher
[  391.826552] CPU: 0 PID: 14412 Comm: insmod Tainted: G           OE      6.8.1+ #2
[  391.834202] Hardware name:  /, BIOS         01.02.01 20240207
[  391.840074] pstate: 63400009 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
[  391.847190] pc : __kmalloc+0x1e4/0x498
[  391.851025] lr : 0xffffc04000000000
[  391.854605] sp : ffff8000a3ab3620
[  391.857987] x29: ffff8000a3ab3620 x28: 0000000000000001 x27: 0000000000000001
[  391.865282] x26: 00000000000001f8 x25: 0000000000aa1d70 x24: ffff00008feac028
[  391.872577] x23: ffffc040aab743f0 x22: ffff80008d4c5020 x21: ffff8000a3ab37f8
[  391.879871] x20: 0000000000000038 x19: ffff8000a3ab3658 x18: ffff8000a3ab3614
[  391.887165] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000004
[  391.894459] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
[  391.901753] x11: 0000000000000000 x10: ffff8000a3ab36a0 x9 : ffffc040c0af8d48
[  391.909049] x8 : ffff00008edc3c40 x7 : 0000000000000000 x6 : 0000000000000000
[  391.916343] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
[  391.923637] x2 : 0000000000000000 x1 : ffff00008e87c480 x0 : ffff00008edc3c00
[  391.930931] Call trace:
[  391.933427]  __kmalloc+0x1e4/0x498
[  391.936899]  0xc0007304e5f6c040
[  391.940107] Code: a9435bf5 a94463f7 910183ff f85f8e5e (d50323bf) 
[  391.946336] ---[ end trace 0000000000000000 ]---
[  391.977579] Kernel panic - not syncing: corrupted shadow stack detected inside scheduler
[  391.980605] kauditd_printk_skb: 98 callbacks suppressed
[  391.980607] audit: type=1400 audit(1713999301.128:108): apparmor="DENIED" operation="open" class="file" profile="rsyslogd" name="/run/systemd/sessions/" pid=801 comm=72733A6D61696E20513A526567 requested_mask="r" denied_mask="r" fsuid=103 ouid=0
[  391.980674] audit: type=1400 audit(1713999301.128:109): apparmor="DENIED" operation="open" class="file" profile="rsyslogd" name="/run/systemd/sessions/" pid=801 comm=72733A6D61696E20513A526567 requested_mask="r" denied_mask="r" fsuid=103 ouid=0
[  391.980679] audit: type=1400 audit(1713999301.128:110): apparmor="DENIED" operation="open" class="file" profile="rsyslogd" name="/run/systemd/sessions/" pid=801 comm=72733A6D61696E20513A526567 requested_mask="r" denied_mask="r" fsuid=103 ouid=0
[  392.057603] SMP: stopping secondary CPUs
[  392.061632] Kernel Offset: 0x404040690000 from 0xffff800080000000
[  392.067859] PHYS_OFFSET: 0x80000000
[  392.071420] CPU features: 0x0,00000000,d002cd4a,2b67fea7
[  392.076848] Memory Limit: none
[  392.106695] ---[ end Kernel panic - not syncing: corrupted shadow stack detected inside scheduler ]---